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In recent years, developing new methods to accelerate orthodontic tooth movement (OTM) has attracted extensive attention in the field of orthodontic clinical and scientific research. It reduces orthodontic treatment time and risks. Over the past, various approaches have been done to accelerate orthodontic tooth movement. Several forms of corticotomy techniques have been effective in inducing rapid tooth movement. These techniques activate regional acceleratory phenomenon and create a favorable microenvironment for accelerating tooth movement. Root resorption is one of most common side effects of orthodontic treatment. It affects the long-term viability and health of teeth. However, the effect of corticotomy techniques accelerating orthodontic tooth movement on root resorption still remains unclear. Accelerating tooth movement may have two-side effects on root resorption. Through shortening the treatment period and removing the hyalinized tissues, the acceleration of orthodontic tooth movement could reduce root resorption. The increase of root resorption might be due to the local inflammation and function of cementoclasts/odontoclasts. In this paper, we reviewed the effects of different corticotomy techniques accelerating orthodontic tooth movement on root resorption. Corticotomy techniques deal with mucoperio-steal flaps and bone tissues differently and develop towards minimally invasive. Previous studies on root resorption use two-dimensional images, including apical films and panoramic tomography, to evaluate the degree of root resorption. In recent years, researches measure the volume of root resorption accurately using cone-beam computed tomography (CBCT) and micro-CT. Most studies suggest that the root resorption during acceleration of orthodontic tooth movement through corticotomy techniques is not statistically different from that of traditional orthodontic treatment. Some studies using micro-CT have shown that the root resorption in the groups of corticotomy techniques increases compared with the control group without surgery. Because of the short duration of these studies, the clinical significance is controversial on the overall impact of corticotomy techniques on orthodontic treatment. Accelerating orthodontic tooth movement is still at its emerging phase and need further research in the form of clinical trials to illustrate the effect of corticotomy techniques accelerating orthodontic tooth movement on root resorption.

Objective: To study the relationship between Sonic hedgehog (Shh) associated single-nucleotide polymorphism (SNP) and non-syndromic cleft lip and/or palate (NSCL/P), and to explore the risk factors of cleft lip and/or palate. Many studies suggest that the pathogenesis of NSCL/P could be related to genes that control early development, in which the Shh signaling pathway plays an important role., Methods: Peripheral blood was collected from 197 individuals (100 patients with NSCL/P and 97 healthy controls). Haploview software was used for haplotype analysis and Tag SNP were selected, based on the population data of Han Chinese in Beijing of the international human genome haplotype mapping project. A total of 27 SNP were selected for the 4 candidate genes of SHH, PTCH1, SMO and GLI2 in the Shh signaling pathway. The genotypes of 27 SNP were detected and analyzed by Sequenom mass spectrometry. The data were analyzed by chi-squared test and an unconditional Logistic regression model., Results: The selected SNP basically covered the potential functional SNP of the target genes, and its minimum allele frequency (MAF) was >0.05: GLI2 73.5%, PTCH1 91.0%, SMO 100.0%, and SHH 75.0%. It was found that the genotype frequency of SNP (rs12674259) located in SMO gene and SNP (rs2066836) located in PTCH1 gene were significantly different between the NSCL/P group and the control group. Linkage disequilibrium was also found on 3 chromosomes (chromosomes 2, 7 and 9) where the 4 candidate genes were located. However, in the analysis of linkage imbalance haplotype, there was no significant difference between the disease group and the control group., Conclusion: In China, NSCL/P is the most common congenital disease in orofacial region. However, as it is a multigenic disease and could be affected by multiple factors, such as the external environment, the etiology of NSCL/P has not been clearly defined. This study indicates that Shh signaling pathway is involved in the occurrence of NSCL/P, and some special SNP of key genes in this pathway are related to cleft lip and/or palate, which provides a new direction for the etiology research of NSCL/P and may provide help for the early screening and risk prediction of NSCL/P.

Objective: To investigate the long-term efficacy of oral appliance treating of obstructive sleep apnea and hypopnea syndrome (OSAHS) in different periods of treatment., Methods: A total of 55 patients were included in the study. Patients were all diagnosed with OSAHS by overnight polysomnography and all received oral appliance (OA) as the therapy. The OA positioned the mandible at 60%-70% of the maximal mandible advancement position and created a 4-5 mm incisor separation. The patients were instructed to wear the appliance during sleep, 6-8 hours per day, for 5-7 days per week. They were divided into four groups by the period of treatment, including less than 1 year group; 1-2 years group; 2-6 years group and 6-9 years group. The polysomnographic study was used to investigate the efficacy of the four groups. The outcome measures included the score on the apnea-hypopnea index (AHI), the longest apnea time and the lowest oxygen saturation (LSaO 2 ) levels during an overnight sleep., Results: The AHI decreased significantly in all the four groups. The less than 1 year group decreased from 24.50 (14.65, 54.05) to 7.40 (2.12,10.00) events/h (P<0.001); The 1-2 years group decreased from 19.50 (12.15, 39.23) to 1.80 (0.70, 6.58) events/h (P=0.001); The 2-6 years group decreased from 25.00 (11.41, 42.60) to 4.50 (1.35, 7.90) events/h (P=0.001); The 6-9 years group decreased from 26.2 (16.95, 47.45) to 4.00 (1.90, 26.70) events/h (P=0.043). The longest apnea decreased significantly in less than 1 year group, 1-2 years group and 2-6 years group. The longest apnea decreased from 57.00 (37.70, 61.50) to 25.00 (15.90, 33.50) seconds (P<0.001) in the less than 1 year group, from 41.00 (25.50, 62.26) to 13.10 (0.00, 22.10) seconds (P=0.001) in the 1-2 year group and from 42.50 (30.35, 58.15) to 15.60 (0.00, 28.10) seconds (P=0.003) in the 2-6 year group. The LSaO 2 levels increased significantly in the less than 1 year group and 2-6 years group. The LSaO(2) levels rose significantly in the less than 1 year group, from 74.18%±7.96% to 84.06%±7.67% (P=0.001), and in the 2-6 years group, from 76.71%±10.98% to 84.06%±4.64% (P=0.006), The LSaO 2 levels did not increase significantly in the 1-2 years and 6-9 years groups. Kruskal-Wallis test showed that there were no statistically significant differences in the AHI, longest apnea time and LSaO(2) in 4 the groups., Conclusion: The oral appliance is an effective therapy for patients with OSAHS in the long-term treatment. However, it's recommended to make appointments with patients as a follow-up supervision whether there is any efficacy decrease. And the oral appliance should be replaced if necessary.

Objective: To investigate the alveolar bone defects of anterior alveolar bone in patients with bimaxillary protrusion by using cone-beam computed tomography (CBCT)., Methods: The samples consisted of 50 patients with bimaxillary protrusion, who were assigned to the teenage group[20 cases, (13.1±1.0) years] and adult group[30 cases, (22.9±4.2) years]. The adult group included 9 hypo-divergent, 11 normo-divergent and 10 hyper-divergent patients. The images were obtained by using NewTom VG CBCT and the alveolar defects were evaluated., Results: The ratio of the patients had alveolar bone defects was 94.00%. Meanwhile, the defects were associated with 38.60% of all the teeth. Most defects occurred on labial alveolar bone (98.66%); fenestration was found more in the maxillary alveolar region and dehiscence occurred more in the mandible. The dehiscences (3.06%) and defects prevalence (30.13%) of the teenage group were significant lower than those of the adult group (11.73% vs. 42.46%), P<0.05; while there was no significance of the fenestrations prevalence between the two group (P>0.05). The hypo-divergent group had lower fenestrations prevalence (22.22%) than the normo-divergent (33.84%) and hyper-divergent groups (37.50%), P<0.05. The upper central incisor had the lowest alveolar bone defect prevalence., Conclusion: Alveolar bone defects are common findings in patients with bimaxillary protrusion before orthodontic treatment. The prevalence of defects is affected by age and vertical-growth type.

Objective: To investigate the agreement of subjective evaluation of orthodontic treatment outcome and to analyze possible factors that may be related to it., Methods: As a randomized clinical trial, with Angle's classification as a stratification factor, our study contained 48 cases with integrity data, which were randomly extracted from 806 orthodontic treatment cases in Peking University School and Hospital of Stomatology during July 2004 and August 2008, and gathered post-treatment study casts, cephalometrics and photographs of the 48 cases as the research subjects. Similarly with Angle's classification as a stratification factor, the 48 cases were randomly divided into 4 groups. According to the monomial and combined subjects, 12 clinicians were asked to act as the raters to rank the 12 cases in each group., Results: Overall, there were 1 584 pairings between the raters in the examination of evaluation. The mean Spearman r was 0.565 3 ± 0.239 9. Grouping factor was related to the agreement of subjective evaluation (P<0.05). In the third trial item-Post-M+P, the correlations were the greatest among the judge-pairs (P<0.001). The other five items were at the same agreement level. The level of orthodontic treatment outcome was a factor that influenced the agreement level of subjective evaluation (P<0.05). The score stability of the patients, whose treatment duration was longer than 2.5 years, was significantly higher than that of the patients whose treatment duration was between 1.5 years and 2.5 years (P<0.05). The following factors, such as Angle's classification, age of patients and whether the teeth was extracted or not, were the insignificant factors (P>0.05)., Conclusion: The average correlations present a moderate agreement level. Grouping, experimental item, the length of treatment duration and the level of orthodontic treatment outcome are the factors that affect the agreement of subjective evaluation. Several factors including Angle's classification, age of patients and whether the teeth is extracted or not, do not affect the agreement of subjective evaluation.

Objective: To assess the consistency of the subjective evaluation of malocclusion severity by the Chinese orthodontic experts., Methods: Sixty-nine Chinese orthodontic experts subjectively evaluated the malocclusion severity for 120 cases which were selected randomly from 6 University orthodontic clinics by checking each case's pretreatment records including study cast, lateral head film, panoramic radiograph, facial photographs and patient chart. Each orthodontist was asked to independently rate the severity of every case into five grades: mild, mildly moderate, moderate, severely moderate and severe. Rating data was finally gathered to evaluate the intra-judge's reliability and the inter-judges' consistency., Results: Weighted Kappa test revealed that 8.33% orthodontists showed excellent intra-judge's reliability (Kappa ≥ 0.81), 78.33% orthodontists showed good intra-judge's reliability (Kappa ≥ 0.61) and 96.67% specialists displayed general intra-judge's reliability (Kappa ≥ 0.41). And intra-class correlation coefficient demonstrated a high level of inter-judges' consistency (r=0.989, P<0.01)., Conclusion: Good intra-judge's reliability and inter-judges' consistency can be demonstrated in the subjective evaluation of malocclusion severity by the Chinese orthodontic experts, which could the basis for establishing the objective grading system of malocclusion severity.

Objective: To investigate the effects of icariin and icariside II on eNOS expression and NOS activity in endothelial cells and possible mechanisms using EGFR over-expressed porcine aorta endothelial (PAE) cell line., Methods: The EGFR gene was transfected into PAE cells and genetic stable cell line (PAE-EGFR) was selected. 12.5 μmol/L of icariin and of icariside II were used to treat the PAE and PAE-EGFR cells respectively for 48 h, the eNOS expression in each group was observed. EGF was also used to treat the cells to observe the regulatory effects of icariin and icariside II on NOS activity. The regulatory effects of icariin and icariside II on NOS activity were also observed, and sildenafil was used as a control., Results: Western blot showed that the basic value of eNOS expression was higher in PAE-EGFR group compared with that in PAE group, both of icariin and icariside II increased the eNOS expression in PAE and PAE-EGFR group (P<0.01), and the value of eNOS expression was higher in PAE-EGFR group than that in PAE group. In the PAE-EGFR cell line, the NOS activity reached (15.37 ± 1.49) u/mg when the concentration of icariside II was 10(-8) mol/L, which was 4.66 u/mg more than that in the PAE cell line. When the concentration reached 10(-7), 10(-6) or 10(-5) mol/L, the change of NOS activity in PAE-EGFR group was greater than that in PAE group (P<0.01). icariin also increased the NOS activity in PAE and PAE-EGFR cells, but the activity was 20% lower compared with icariside II group, however, Sildenafil showed no influence on NOS activity., Conclusion: Icariin and icariside II may increase the eNOS expression through activating EGF-EGFR pathway in PAE cell, by which endothelial cells function could be regulated and the better effect was noted in icariside II compared to icariin.

Objective: To investigate the changes of morphology and steroidogenic function in aged human Leydig cells and to understand the mechanism of late onset hypogonadism (LOH)., Methods: Ten young and ten aged male subjects were enrolled in this study. AMS (Aging Male's Symptoms) scale was used for symptom evaluation. Testes species with LOH were utilized as the research model. Then the histological changes in testis and ultrastructure of Leydig cells were observed by HE staining and electron microscopy (EM), respectively. The serum total testosterone concentrations were measured by an ELISA kit. The expressions of steroidogenic acute regulatory (StAR) protein and cholesterol-side-chain cleavage enzyme (P450scc) were detected by western blot., Results: The scores of AMS in the aged group were higher than those in the young group with decreased serum testosterone levels (61.25 ± 7.08 vs. 20.75 ± 3.73,P<0.001). And the serum testosterone level of the aged human was lower than that of the young human [(3.12 ± 0.58) μg/L vs. (6.29 ± 1.17) μg/L,P<0.05]. HE staining showed that degenerative changes occurred in the aged human testes. And many swollen mitochondria with mitochondrial cristae that disappeared were found in Leydig cells of the aged human by EM. The serum total testosterone level of the aged human was significantly lower than that of the young group. And the expressions of StAR and P450scc protein in the aged group were significantly lower than those of the young group., Conclusion: Mitochondrial swelling and decreased expressions of StAR and P450scc were closely related to the reduced ability of testosterone synthesis in aged males. And the exact mechanism needs further investigation.

Objective: To investigate the clinical efficacy and patient and partner's satisfaction with penile prosthesis implantation (PPI) for treating Chinese patients with severe erectile dysfunction (SED)., Methods: One hundred and sixty-eight SED patients were successfully treated by PPI from July 2000 to June 2010. Of the 146 (86.9%) patients who had been followed up over 6 months post-operation, 36 (24.7%) had been implanted with one piece malleable prosthesis (AMS650) and 110 (75.3%) with three piece inflatable prosthesis (AMS700CXM).All the patients had been followed up by using international index of erectile dysfunction (IIEF5), Quality of Life Score (QOL) for evaluating clinical efficacy and using Visual Analogue Scale (VAS) for evaluating patient and partner's satisfaction and the duration of the follow-up was 6 to 119 months., Results: The mean age of patients was 35.9+/-12.1 years(20 to 75 years), All the operations were successful and sexual intercourse with PPI was performed post 4 to 6 weeks without severe complications like infection and erosion. The prosthesis survive rate and frequent sexual intercourse rate were 98.6% and 87.7% respectively. IIEF5 scores pre and post PPI were 6.3+/- 1.7 and 21.3+/-1.6 respectively,the QOL scores pre and post PPI were 5.1+/-0.9 and 1.5+/-0.5 respectively, and both of them showed significant improvement (P<0.01). As for VAS, the patient and partner's overall satisfaction rates were 92.5% and 90.4% respectively. Moreover, better satisfaction was showed with AMS700CXM as compared with AMS650 (P<0.05) in patients with SED., Conclusion: PPI is the safe and effective treatment option for Chinese patients with SED. The AMS700CXM penile prosthesis is better than AMS650 for patients' overall satisfaction.

Objective: To investigate the efficacy and safety of corpus cavernosum-corpus spongiosum shunt (CC-CSS) plus intracavernous tunneling(CC-CSS+ICT) for the treatment of prolonged ischemic priapism (PIP) were investigated., Methods: Of 21 patients with PIP, 11 (Group A) underwent CC-CSS and 10 (Group B) CC-CSS+ICT surgery. The penile hardness score (PHS) and pain visual analogue score (PVAS) were used to assess the efficacy of the surgery., Results: The erectile functions of the two groups were normal (IIEF5 23.6+/-1.1) before the onset of PIP, and the duration of PIP was (3.4+/-1.3) d. PHS 3.9+/-0.4, and PVAS 8.4+/-0.7. There was no statistical difference between the two groups (P>0.05). On 1, 3 and 5 days after the operation, the PHS and PVAS of Group B decreased significantly than those of Group A (P<0.05)., Conclusion: CC-CSS+ICT could quickly restore penile detumescence and relieve pain as compared with CC-CSS, which might be a safe and effective method for the treatment of PIP.